Emit a single destructuring assignment for destructuring declarations,
which can be desugared by the bytecode generator. This allows us to
remove destructuring desugaring from the parser (specifically, the
pattern rewriter) entirely.
The pattern "rewriter" is now only responsible for walking the
destructuring pattern to declare variables, mark them assigned, and
potentially rewrite scopes for the edge case of parameters with a sloppy
eval.
Note that since the rewriter is no longer rewriting, we have to flip the
VariableProxy copying logic for var re-lookup, so that we now pass the
new VariableProxy to the variable declaration and leave the original
unresolved (rather than passing the original through and rewriting to a
new unresolved VariableProxy).
This change does have some effect on breakpoint locations, due to some
of the available information changing between the parser and bytecode
generator, however the new locations appear to be more consistent
between assignments and declarations.
Change-Id: I3a58dd0a387d2bfb8e5e9e22dde0acc5f440cb82
Reviewed-on: https://chromium-review.googlesource.com/c/1382462
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: Adam Klein <adamk@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: Yang Guo <yangguo@chromium.org>
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58670}
Goal of this CL: explicit return from non-async function has position after
return expression as return position (will unblock [1]).
BytecodeArrayBuilder has SetStatementPosition and SetExpressionPosition methods.
If one of these methods is called then next generated bytecode will get passed
position. It's general treatment for most cases.
Unfortunately it doesn't work for Returns:
- debugger requires source positions exactly on kReturn bytecode in stepping
implementation,
- BytecodeGenerator::BuildReturn and BytecodeGenerator::BuildAsyncReturn
generates more then one bytecode and general solution will put return position
on first generated bytecode,
- it's not easy to split BuildReturn function into two parts to allow something
like following in BytecodeGenerator::VisitReturnStatement since generated
bytecodes are actually controlled by execution_control().
..->BuildReturnPrologue();
..->SetReturnPosition(stmt);
..->Return();
In this CL we pass ReturnStatement through ExecutionControl and use it for
position when we emit return bytecode right here.
So this CL only will improve return position for returns inside of non-async
functions, I'll address async functions later.
[1] https://chromium-review.googlesource.com/c/543161/
Change-Id: Iede512c120b00c209990bf50c20e7d23dc0d65db
Reviewed-on: https://chromium-review.googlesource.com/560738
Commit-Queue: Aleksey Kozyatinskiy <kozyatinskiy@chromium.org>
Reviewed-by: Adam Klein <adamk@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46687}
This refactoring makes it easier to write advanced tests and
gives full control over what's happening to the test code.
It also forces description for every test.
BUG=none
Review-Url: https://codereview.chromium.org/2891213002
Cr-Commit-Position: refs/heads/master@{#45412}
